Thank you for the replies - Understood where i went wrong.
LCM of 6 and 8 is 24
Therefore 24/6=4 so the marks are {4,8,12,16,20}
Therefore 24/8=3 so the marks are {3,6,9,12,15,18,21}
Least possible distance is 1/24
Therefore least possible distance in meters = (1/24)*100 = 4.16
B
LCM of 6 and 8 is 24
Therefore 24/6=4 so the marks are {4,8,12,16,20}
Therefore 24/8=3 so the marks are {3,6,9,12,15,18,21}
Least possible distance is 1/24
Therefore least possible distance in meters = (1/24)*100 = 4.16
B